[Failure of correction of deformities of the cervical spine after intervertebral spondylodesis]

In an effort to reveal the mechanism and the causes of loss of achieved deformation correction during postoperative period in case of intervertebral spondylodesis of cervical part of vertebral column there has been undertaken an investigation, based on detailed clinical and roentgenologic analysis of 69 operated patients in dynamics, combined with the experimental investigations at the intervertebral spondylodesis model. In all patients there has been stated the loss of originally achieved correction, differing in value and direction. It has been suggested that the main loss of correction is, for the most part, a single-stepped and intermittent event, that occurs, as a rule, in the near postoperative period. The system tendency to reach the state of stable equilibrium under the effect of arising external forces turned out to be the mechanism of losses and the main cause is inadequate primary stabilization of the created block. A hypothetic classification of the functional state periods of the operated cervical part of vertebral column has been derived. The main advantages of +ceramic spondylodesis as compared with osteoplastic one have been revealed. There have been determined the necessity of further improvement of endofixative construction and surgical intervention techniques, aimed at the primary stabilization level increase.